"I am a pro-choice, pro-environment, pro-Bill of Rights Republican, and I will be voting against this nomination," Chafee said in a statement. However, Chafee said he will not support Democratic attempts to sustain a filibuster on Alito.

Chafee's unwillingness to toe the party line complicates his chances at reelection this fall. His "no" vote on Alito provides Cranston Mayor Steve Laffey (R) considerable fodder for his challenge to Chafee in the state's Sept. 12 primary. Republicans and independents can vote in the primary, but not Democrats. Laffey has already come out in support of Alito and called on Chafee to follow that lead.

Chafee's decision shocked many in the Republican political world who believed that the senator understood the political realities associated with the Alito vote.

One GOP strategist said Chafee even had cover for a "yes" vote, pointing to a Providence Journal editorial supporting Alito's confirmation and the support Alito has garnered from other pro-abortion rights Republicans, including Sen. Arlen Specter (R-Pa.), the chairman of the Senate Judiciary Committee. Several Democrats have also said they will support Alito's nomination, including Sens. Robert Byrd (W.Va.), Tim Johnson (S.D.) and Ben Nelson (Neb.).

Chafee has never been a favorite of Republicans in the state given his willingness to buck the party establishment on key issues -- including his decision not to vote for President George W. Bush in 2004 (instead, he said he wrote in the name of former President George H.W. Bush.).

Lincoln Almond, the former Rhode Island governor who appointed Chafee to the Senate in 1999, expressed dissatisfaction with Chafee's decision on Alito. "I am disappointed with Senator Chafee's decision not to support Judge Alito," said Almond. "I had to opportunity to meet with the senator on Judge Alito, so I understand his position."

Almond is heading up the Rhode Island effort to confirm Alito.

Republican strategist sympathetic to Laffey's primary challenge said it was an "embarrassment that national Republican leaders are trying to bail this guy [Chafee] out." The National Republican Senatorial Committee has run several ads bashing Laffey's record as mayor, and NRSC Chairwoman Elizabeth Dole (N.C.) has been outspoken in her support of Chafee.

Laffey, too, has powerful allies on his side -- most notably the Club For Growth, a D.C.-based group that backs fiscally conservative candidates. The Club is spending $100,000 on a flight of television and radio ads designed to introduce Laffey to the state's electorate. The television commercial is a bio spot that touts Laffey's work to save Cranston from bankruptcy; the radio ad takes Chafee to task for allegedly voting with Sens. John Kerry (D-Mass.) and Hillary Rodham Clinton (D-N.Y.) more than 60 percent of the time.

Should Chafee get past Laffey in the primary, his opposition to Alito seems likely to strengthen his hand in a general election as he seeks to cast himself an an independent voice for the state. Former state Attorney General Sheldon Whitehouse and Secretary of State Matt Brown are running for the Democratic nod.

Democratic Senatorial Campaign Committee spokesman Phil Singer said Chafee's decision is another reason why the Rhode Island Republican should be voted out in the fall. "This is a lifetime appointment to the Court and he hid in the political shadows," said Singer. In other words, Chafee should have been a more forceful opponent of Alito within the GOP conference.